The present invention relates to a stretching mechanism of a device for cutting slaughtered poultry, said mechanism being provided with a support member with a support face for the bird, with means to hang the bird by the legs, with fixed hooks for the wings of the bird and with movable wing hooks cooperating therewith and with means to hold the trunk of the bird on the support face, said holding means including a movable centering fork, which is oparable to engage the spine of the bird at the inside of the trunk and which is vertically and horizontally movably guided in guide slots in the support member between an inoperative position and an operative position by means of a guide bar and two transverse bars fixed thereto.
Such a stretching mechanism is described in U.S. Pat. No. 4,505,002. In this earlier proposed stretching mechanism the fixed wing hooks which are fastened to the support member cooperate with the movable wing hooks which are fastened to triangular supports of the centering fork on the guide bar. The bird is firstly hung by its knee-joints onto U-shaped suspension hooks and the wings are hooked below the fixed wing hooks. When the centering fork moves to its operative position, the wings of the bird are locked against the fixed wing hooks by movable wing hooks of the centering fork. However, with this mechanism the wings of the bird should be pulled rearwardly by hand, which requires a rather great effort. This involves loss of time and reduces the production rate of the cutting device.
The present invention tends to abolish the disadvantages of this earlier proposed stretching mechanism.
This object is achieved in that in accordance with the invention the movable wing hooks are provided with a slotted member for the wings of the bird and with a cam surface, which during the movement of the centering fork cooperates forcedly with a part fixed to the centering fork, such that the slotted member is open in the inoperative position of the centering fork and cooperates to hold a wing with the fixed wing hook in the operative position of the centering fork.
By applying these measures, the wings of the slaughtered birds can be hooked without effort in the slotted members of the movable wing hooks and can be released by the person loading the mechanism, whereafter the movable wing hooks swing into their operative position where the wings of the bird are locked in the slotted members of the movable wing hooks by the fixed wing hooks. Therewith an increase of the production rate of about 25% is obtained, i.e. that with the stretching head in accordance with the invention about 300 birds more can be hung per hour than with the earlier porposed stretching head in accordance with U.S. Pat. No. 4,505,002.
The invention will be further elucidated with the aid of some embodiments on the basis of the drawings.